Die-casting machine



Aug. 22, 1950 E. A. BUTNER 2,519,

.DIE CASTING MACHINE Filed Sept. 4, 1946 4 Sheets-Sheet l IN VEN TOR.

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DIE CASTING MACHINE Filed Sept. 4,-1946 4 Sheets-Sheet 2 INVENTOR.

Y 004! A. El fA/ER A 7' TOP/VEYS Aug. 22, 1950 E. A. BUTNER 2,519,739

DI'E CASTING MACHINE I Filed Sept. 4, 1946 4 sheets-sheet s INVENTOR. 04R A Ear/viz BY 4 T TOPNFYS Patented Aug. 22, 1950 UNITED STATES PATENT OFFICE DIE-CASTING MACHINE Edgar A. Butner, Brooklyn, N. Y., assignor to Hydropress, Incorporated, New York, N. Y., a corporation of Delaware Application September 4, 1946, Serial No. 694,768

Claim.

This invention relates to die casting machines or the like and particularly to an automatic feeding device and machine control.

In die casting machines, molten metal is fed to a pressure cylinder, said cylinder communicating with the interior of a die and after metal has been placed in the pressure cylinder, a ram is engaged in said cylinder to force the molten metal into the die. Following filling of the die, excess metal will be present in the pressure cylinder and must be removed and thereafter the die is opened and the cast article taken out.

One of the objects of the invention is to provide a device for automatically feeding molten metal from a reservoirto a cold casting chamber in a more eflicient manner than previous devices and. to remove the excess solidified metal after an object has been cast so that the cycle of the machine can-be repeated.

Another object of the invention is to provide a control for the die casting cycle which can be operated with ease and will be automatic in functioning during various portions of the operation.

One of the features of the present apparatus is a ladle and cooperating pouring trough or guide, said trough moving to a pouring position over the pressure cylinder as the ladle moves from the molten metal reservoir to a metal pouring position. A valve in the ladle is operated to release metal therein when the ladle contacts the trough when the trough is in its metal pouring position. An excess metal slug removing device is moved to a latched or cooked operating position by the trough and is thereafter released at an appropriate time to remove an excess metal slug, the solidified slug having been moved to a position in front of the removing device by a cutofl' piston in the pressure cylinder. The cutoff piston first has the function of cutting off the nozzle or passage between the pressure cylinder and the die chamber and thereafter moving a. solidified slug of excess metal upwardly to a position to be acted upon by the slug remover.

The control circuit can be arranged so that a single push button or controller may be used to initiate operation of the various portions of the cycle. At the first depression of the switch, the machine automatically operates to close the dies, feed molten metal to the pressure cylinder, and cock the slug remover. At a second operation of the push button, the pressure ram is given a pressure casting stroke and thercutofl piston is operated to close off the nozzle leading to the die chamber; The excess metal is raised after a predetermined time to a position in front of the slug remover and at this time, the slug remover is tripped so as to remove the excess metal slug from the path of the ram. The dies then are opened so that the casting can be removed and the machine is in readiness for the next casting operation. It is understood, of course, that various materials can be cast or operated upon in suitable machines although the present invention is especially adapted for the cold chamber casting of relatively low melting alloys such as zinc and the like.

These and other objects, features, and advantages of the invention will become apparent from the following description and drawings which are merely exemplary.

In the drawings:

Fig. 1 is a diagrammatic view, partially in section, of one form of the machine.

Fig. 2 is an enlarged plan view taken along the line 2-2 of Fig. 1.

Fig. 3 is a fragmentary enlarged view of the ladle and trough in pouring position.

Fig. 4 is a schematic view of one form of wiring diagram that may be used in conjunction with the operation of the device.

In a preferred embodiment, the machine comprises a crucible II for molten material which may be heated in any conventional manner. Ladle I2 is suspended by means of rods or elements it from a slidable sleeve 49 carried by pivoted pin it, said pin being pivotally supported at l5 to rotatable arms l6. Arms l6 are mounted on shaft I1, said shaft having a pinion It attached thereto, said pinion It being operable by rack It, the rack in turn being reciprocable by a motor such as the hydraulic cylinder arrangement 20. Mounted at the ends of the shaft I! are pinions 2|, said pinions being engageable with racks 22, the racks being mounted on cross arm 23. Cross arm 23 is slidably mounted on guide rods 2|, said guide rods being fastened to frame 28'. Material pouring trough 28 also is mounted on the cross arm 23, said trough having a ladle contactingring 21. Ladle l2 preferably is bottom pouring and has a valve 41 cooperating with an aperture 48 in the bottom thereof, said valve being fastened to pin ll.

When arms I6 are rotated counterclockwise (Fig. 1) to the position shown in Fig. 3, trough 28 will be moved from a retracted position to a feeding position over pressure cylinder 28. Ladle bowl l2 will come to rest on ring 2'! of the trough top and additional movement of arms I6 after the ladle has come to rest will cause pin It to move downwardly relative to sleeve 49 and thus open valve 41 to allow molten metal 50 to flow into trough 26 for feeding to pressure cylinder 28.

Vertical pressure cylinder 28 is mounted on the main frame 28 of the machine for receiving metal from the trough. said cylinder having a nozzle 29 leading therefrom to conduct metal from the pressure cylinder to die 30. Cutofi piston 3| is slidable within pressure cylinder 28, said piston normally being positioned to cutoff the contents of pressure cylinder 28 from nozzle 29, spring 32 normally maintaining piston 3| in the upper position shown in Fig. 1. The other half of the die is seen at 33 and is carried by movable plate 34, said plate being reciprocable by piston 35 of hydraulic cylinder 36. into pressure cylinder 28 for forcing metal therein into the closed dies and is operated by hydraulic piston 38.

Tracing the operation of the pressure cylinder and die arrangement during a casting operation, metal is poured into cylinder 28 from trough 25 and then piston 31 descends so as to force metal in cylinder 28 downwardly along with piston 3| until nozzle 29 is uncovered. At this time, the metal will be forced into the dies so as to enter the die chamber formed by closed dies 30 and 33, spring 32 yielding during this operation so as to allow piston 3| to move downwardly. After the casting operation is complete, piston 31 will be raised upwardly, piston 3| being moved back to the position shown in Fig. 1 by spring 32, which will serve to cut off the excess metal at nozzle 29. The excess metal in cylinder 28 then is permitted to solidify, and following th s, hydraulic cylinder 39 will operate bell crank lever 39' to move the piston 3| upwardly until the solidified excess metal slug is above face 40' of the frame of the machine or above the-top of the pressure cylinder 28.

In order to remove the solidified excess metal slug from the path of the piston and pouring mechanism,- a slug remover is provided. The slug remover 40 is seen in a cocked position in Fig. 1 where it previously has been moved by the trough as will be explained hereafter so that band 4| thereof is clear of the bore of the pressure cylinder 28. Remover band 4| is fastened to guides 42, said guides being slidable in members 43. Springs 44 normally urge the slug remover band 4| to the right, Fig. 2 showing the,

remover in its cocked or energized position. The remover is held in cocked position by means of latch or latches 45 which can be moved to inoperative position by solenoids 45. When solenoids 46 are energized, latches 45 will be moved downwardly so that the force of springs 44 will project the slug remover band 4| rapidly to the right thereby carrying a slug from the top of piston 3|, then in its elevated position in pressure cylinder 28.

Main ram 31 is enterable The slug remover 40 can be moved into a. cocked position by cams extending downwardly from trough 26 contacting the cross bar 6| so as to compress springs 44 as the trough 26 moves to the left (Figure 1).

The various hydraulic mechanisms may be controlled by four-way hydraulic valves 5|, 52, 53, and 54 in a well known manner. These valves have suitable solenoids as will be described for moving a valve in one direction and a return spring for moving the valve in an opposite direction when the solenoid is deenergized.

As one example of a circuit for automatic operation of the cycle of the die casting apparatus.

reference may be made to Fig. 4 cf the drawings. The circuit is arranged so that two operations of a single push button or controller may be used to initiate and complete the entire cycle. The cycle initiated upon a first pressing of the push button includes closing of the die, and simultaneously with said closing, causing the transfer of metal from the crucible to the die casting cylinder. The ladle in this case starts to rotate at the same time the trough is moving into pressure cylinder filling position.

When the pouring of the metal into the die casting cylinder has been completed, the push button is operated a second time to initiate the return of the trough and ladle to a position away from the pressure cylinder, and to move the casting ram or pressure applicator downwardly into the pressure cylinder. A timing circuit also is energized at the second operation of the push button which will initiate return of the ram to its first inoperative position from the pressure or casting position after a predetermined time. The cutoff piston is raised after the casting operation to move upwardly a solidified excess metal slug in the vertical pressure cylinder. After the slug has been moved upward to the top of the cylinder, a further circuit is energized to remove the slug therefrom. Another timer circuit, which was energized at the second operation of the push button, will cause opening of the die after a predetermined time and will clear the various circuits in readiness for the next operation of the machine.

Specifically, push button elements I00 and IN are connected together mechanically so that switch I00 is normally open and switch IN is normally closed. The main power leads are indicated at I02 and I03 with amain operating switch I04 which can be closed before the machine is to be operated.

For convenience, the various operating coils are numbered and contactors operated thereby are given a similar number and a distinguishing letter so as to indicate contactors operated by a correspondingly numbered coil. The contacts which are shown as being open in the diagram are normally open and those indicated as being closed are normally closed, a coil upon energize.- tion changing the position of the contact from that shown in the drawing.

With switch I04 closed, a first operation of push button I 00 will complete a circuit therethrough from lead I02 to I03 through switch operating coil I05. Energization of coil I05 will close five normally open contacts, |05a to I05e. Holding contact I 05a will complete a holding circuit around push button I00 so that coil I05 will remain energized when push button I00 is released the first ime. Die control contact I05e is closed to energize solenoid I05 controlling the four-way valve 5| for initiating closing of the dies.

Contact I05d is closed to energize ladle switch coil I01 through normally open contact I0Ia to energize solenoid I09 and move valve 52 to admit pressure to cylinder 20 to commence operation of the ladle I2 from crucible l I and movement of the trough-25 toward the vertical'cylinder 28. Movement of trough 26 to the left will engage slug remover 4| and move the same therewith until latch 45 is forced upwardly by spring 55.

Contact |05b is closed so that when the push button is released, IOI will close (having been opened by depression of I00) and thus complete the circuit from I02 through IOI, switch I051),

- coil m to lead us. Coil m closes switches in preparation for the second operation of the push button and remains closed until II! is deenergized by timer H2 at the completion or the casting cycle. Energization oi coil III will close holding switch IIlb serving as a holding circuit therefor. Contact Illa is closed so that the circuit including ram operating switch coil I II is prepared for the next operation of the push button. Contact Illc is' opened so as to separate the circuit containing coil Ill from the circuit containing coil III. 1

Upon the next operation of push button Ill, a circuit will be established through la and ram operating switch coil III. Contact Illa will serve as a holding circuit for coil III. Contact IIIc will cause energization of timer operating switch coil Ill, Illc having been closed by coil Ill. This will close holding contact Illb and timer circuit contact Illa and will open normally closed contact Illc thus deenergizing ladle switch coil Il'l. Deenergization of ladle switch coil ill will deenergize ladle valve solenoid Ill and thus cause operation of ladle valve 52 to start return of the ladle and trough away from the pouring position. The closing of contact Illa will complete a circuit to the cycle completion timer 2 and ram timer Ill, said timers being of any suitable variety such as one of the conventional adjustable electronic type if desired.

Ram operating contact IIId will be closed to energize ram valve solenoid I so as to cause operation of ram control valve 53 to admit fluid under pressure to move ram 31 downwardly. After a suitable time delay. ram timer Ill will cause coil III to be energized so as to open contact Illa thus deenergizing coil III. This will open-contact Illd and deenergize ram valve solenoid I25 so that the ram 31 will be moved upwardly again after the die casting operation. During the downward movement of the ram, cutoi! piston ll is forced downwardly by. ram 31 and as ram 31 moves upwardly, the piston also will move upwardly and shear off the metal at the nozzle 29 thus separating the casting from the metal remaining in'pressure cylinder 28. Contact Illb will be closed by coil Ill so as to energize cutoff piston elevating timer H5 to elfect a suitable time delay suflicient to allow the metal remaining in pressure cylinder 28 to solidify.

Energization of timer coil Ill will close contact Illa so that when the ram 31 reaches its upper position, ram limit switch III will be tripped and closed so as to establish a contact through cutofl piston valve solenoid ill to cause operation oi. cutoff piston elevating valve 54 to admit fluid under pressure to cutoff elevating piston 39. The purpose of timer 5 is to insure a suflicient time delay to permit the excess metal to solidify so that even though the ram has tripped the limit switch that valve 54 will not be operated until sufllcient time has elapsed to allow the excess metal to solidify.

When cutofl iston lI has brought a slug to the top of the cylinder 28, cutoilf piston limit switch II! will be tripped closing a contact and energizing coil I2ll. Slug remover latch trip switch I2lb will be closed to energize latch trip coil ll and release thelatch. Contact 120a will be closed to start cutofl piston return timer I2I which after a suitable time will energize coil I22. Opening of contact I22a deenergizes cutoff piston solenoid ill to permit operation of valve It so that cutofl piston 3| again will move to the 8 lower position shown in Fig. 1. When the cutofl piston ll has dropped, cutoil piston limit switch Ill will have been released so as to deenergize coil I20 thus opening latch contact I2lb and deenergizing solenoid ll preparing the latch for the next operation of the machine. Simultaneous with the cycle completion, the previously mentioned timer II2, which was energized when the push button was operated the second time, operates to energize coil I24 to open switch I2la deenergizing coil Ill which was energized when the push button was closed the first time which opens all the Ill contacts so that all switches are restored to the position shown in Fig. 4 ready for the next die casting operation. Solenoid Ill will be deenergized so that valve II will cause the dies to be opened. Thus the cycle of die casting can be controlled by pushing the same switch twice and the cycle will automatically be carried out and upon completion the device will be in a position to have the cycle repeated for the next die casting operation. The push button or controller may be operated manually or mechanically in any well-known manner or separate controllers may be employed.

The details of construction shown are illustrative of one form of the invention and variations may be made therefrom without departing from the spirit of the invention as defined in the appended claims.

It is claimed:

1. In an apparatus for transferring metal from a melting pot to the injection cylinder of a cold chamber die casting machine or the like, the combination comprising a, bottom pour transfer receptacle bodily movable from said melting pot to a delivery point, said delivery point being remotely located relative to said melting pot, a separate molten metal guide slidably mounted relative to said injection cylinder for receiving metal from saidreceptacle at said delivery point 'and conveying said metal to said injection cylinder, and guide and receptacle moving means moving said guide and receptacle in coordinated relationship to and from said delivery point so that said guide is in position to direct metal to said injection cylinder from said transfer receptacle when both are at said delivery point and the guide is clear of the injection cylinder when injection takes place.

2. In an apparatus for transferring metal from a melting pot to the injection cylinder of a cold chamber die casting machine or the like, the combination comprising a transfer receptacle bodily movable from said melting pot to a delivery point, said receptacle receiving molten metal from said melting pot and carrying the same to .said delivery point, a normally closed valve in the bottom of said receptacle, 2. separate molten metal guide slidably mounted relative to said injection cylinder, means moving said guide and receptacle to and from said de- -livery point so that said guide is in position to direct metal to said injection cylinder from said transfer receptacle when both are at said delivery point, and automatic valve opening means to open said valve after said receptacle reaches said delivery point to deliver molten metal to said guide.

3. In an apparatus for transferring metal from a melting pot to the injection cylinder of a cold chamber die casting machine, said machine having a die member and an injection cylinder connected to said die, a bottom pour ladle bodily movable from said melting pot to a position adjacent said injection cylinder for transferring metal from the melting pot to the injection cylinder, a separate trough slidably mounted relative to said injection cylinder for conveying metal from said ladle to said injection cylinder when said ladle is adjacent said injection cylinder, said ladle and trough being movable to and from a position adjacent said injection cylinder for delivery of metal to the injection cylinder when both are located in a delivery position adjacent said injection cylinder, and means applying preschamber die casting machine or the like, said machine having a die member and an injection sure to said injection cylinder for forcing metal into said die after said ladle and trough have delivered metal to said injection cylinder and have been moved away from said position adjacent said injection cylinder.

4. In an apparatus for transferring metal from a melting pot to the injection cylinder of a cold chamber die casting machine or the like, the combination comprising a transfer receptacle pivotally mounted on an oscillatable arm means, said receptacle being bodily movable from said melting pot to a delivery position, said receptacle receiving molten metal from said melting pot and carrying the same to said delivery position, a normally closed valve in the bottom of said receptacle, a, separate molten metal guide slidably mounted relative to said injection cylinder, gear and rack means interconnecting said guide and said arm means to move the same to and from said delivery position so that said guide is in position to direct metal to said injection cylinder from said transfer receptacle when both are at said delivery point, and automatic valve opening means to open said valve after said receptacle reaches said delivery position to deliver molten metal to said guide.

5. In an apparatus for transferring metal from a melting pot to the injection cylinder of a cold cylinder connected to said die, the combination comprising a ladle bodily movable from said melting pot to a delivery position adjacent said injection cylinder, said ladle having a valve mechanism therein adjacent the bottom thereof and movable relative thereto, a ladle moving mechanism connected with said ladle and valve, a separate trough conveying metal from said ladle to said injection cylinder, operating means moving said ladle moving mechanism, ladle, and trough to and from a cylinder delivery position, means to arrest movement of said ladle in a delivery position, and means moving said ladle moving mechanism beyond said delivery position of the ladle, so as to move said valve mechanism relative to said ladle to deliver metal from said ladle to said trough from which it is delivered to said cylinder.

EDGAR A. BUTNFR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

